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Memoirs of the National Museum of Victoria 1 May 1962 https://doi.org/10.24199/j.mmv.1962.25.15 REVISION OF GENUS THOPHA 269 R1S5§S?t5F THE ™NUS THOPHA AMYOT AND SERVILLK CICADIDAE, DIVISION THOPHARIA HOMOPTERA-HEMIPTEK A By A. N. Burns 3H.Se., F.R.E.S., Curator of Insects, National Museum of Victoria Abstract This genus erected by Amyot and S-erville (1843) contains four species one of which (saccata) has been known for over 150 years. Prior to 1904 the genus contained four species, but in that year Distant erected the genus Arunta to which he transferred two species. In 1907 and 1910 respectively Distant added two more species to Thopha bringing the total back to four species. The main differences between Arunta and Thopha have already been set out under Arunta, it should be added however that in Thopha the eyes are strongly pedunculate. Two of the species rank probably as the two largest cicadas in Australia, and they are similar in size and pattern of markings. Introduction The geographical distribution of the genus is interesting, two species {saccata and sessiliba) occur near the coast where the rainfall exceeds thirty inches a year, it is possible also that nigricans occurs in a region of similar rainfall, but colorata is definitely a dry country species; saccata is found in eucalyptus forest in a wide coastal strip from a little south of Sydney to some distance north of Brisbane, and at Mareeba on the Atherton Tableland. Sessiliba has a coastal as well as inland range of distribution being found in savannah forest; it ranges from southern Queensland (Gatton, Brisbane) along the coast of northern Australia to Wyndham, and in inland districts ranging from the Northern Territory (coastal) to Batchelor and Tennants Creek to Mundiwindi in Western Australia. Both species are at times very abundant, and are referred to as " Double Drummers " on account of the loudness and penetrating qualities of their song. They seem to prefer eucalyptus and angophora trees, and often climb to the uppermost branches of high trees especially if the weather is sunny. In warm dull weather how- ever specimens may often be taken from the trunks of both large and small trees at heights only a few feet from the ground. T. colorata has an interesting range of distribution which appears mainly to follow a strip running across Die continent from near Alice Springs to Carnarvon on the coast of Western Australia. I have been informed that it frequents fairly large frees, mainly eucalyptus. For information about T. nigricans I am indebted to Mr. Izzard of the British Museum (Natural History) for figure and structural details. 270 REVISION OF GENUS THOPHA Summary of External Morphology, General: Very large Insects with robust bodies of which the length is a little over twice the width; the anterior wings approximately one and a quarter times body length. Body reddish brown or yellowish brown marked mainly with black, tympanal sacs very large but not covered with white (omentum. Wings clear vitreous, head sculptured, almost devoid of pubescence, slightly wider I ban pronotum, eyes pedunculate, ocelli small and grouped closely together, distance between two posterior almost twice that between anterior and each posterior, Irons rather weakly and obtusely convex, grooved In front, rostrum extending to posterior coxae. Thorax with width of pronotum twice its length, sculptured, three sulci on either side of median, posterior margin well developed, very slightly concave, mesonotum almost smooth, cruciform elevation clearly but not strongly developed, rounded apically, metanotum only partly visible dorsally. Anterior femora not strongly developed, bearing two sharply pointed spines. Posterior tibiae normally with five or six spines; length of anterior wings just exceeding three times their width; of posterior, twice. Abdomen smooth, slightly pubescent dorsally on first thre,e segments, .sparingly on medians, fairly dense 7-9. Operculae small, (slightly larger than in Arunta) interior margins separated, exterior recurved; tympanal sacs very large and extending laterally almost to segment four. Remaining abdominal segments compressed. Measurements of each species are given with description. Genotype: Tettigonia saccata Fabr. 1803, " Syst Rhyng.": 34-9. Key to the species of Thopha. 1. Wings clear Vitreous, eyes pedunculate, head wider than pronotum, tympanal sacs (males) extending laterally almost to fourth abdominal segment .. .. .. .. ..2 2. (I) Head with a black transverse band between eyes enclosing ocelli; anterior to this a yellowish brown transverse band of similar width; fron.s (excepting vertex), genae. and ventral surface of head, black colorata Head and frons not banded transversely, ocelli almost equidistant and same colour as head, vitreous . 3 3. (1) Head, including Irons, uniform deep purplish brown, posterior tibiae* with six spines (male) nigricans Head not o{ uniform colour, ocelli not same colour as head .. 4 4. (I) Head black, a narrow Interrupted yellowish brown band across front, a similar band across back of head, ocelli small, dark red vitreous saccata Head not black or unicolorous, ocelli not equidistant and of same colour as vertex of head . 5 5. (I) Head reddish brown with light plum coloured suffusion, a pale yellowish transverse band across front, legs unicolorous with tympanal sacs sessiZiba REVISION OF GENUS THOPHA 271 THOPHA COLORATA Distant. Thopha colorata Distant, 1907.—Ann. Mag. Nat. Hist (7), 20: Thopha colorata Ashton, 1914.—Trans. Boy. Sue. S. AusL, 38: 3-16. Thopha colorata Ashton, 1921.—Proc. Roy. Soc. Vict. (N.S.), 33: 89. This species is apparently not rare but rather local and is a dry country cicada. All specimens examined by the writer came from Aliee Springs, Hermannsburg, and Carnarvon W.A.. and label data indicates that it is an early summer species, November and December. Average body length, male, 38-6 mm., female, 38-2 mm.; maximum of specimens examined, males, (12) 42- mm., females, (3) 39- mm.; minimum, males, 37* mm., females, 37-5 mm. Head yellowish brown with a black transverse bar between eyes enclosing ocelli, sculptured with numerous longitudional grooves, a median sulcus from anterior ocellus to posterior margin. Frons black with yellowish brown vertex, front with a wide median, longitudional groove, normally ten transverse ridges visible, interstitial depressions with very short greyish pubescence. Ocelli garnet vitreous, not equidistant, anterior in midline of eyes. Genae black, lightly invested with fine greyish pubescence. Antennae black; clypeus black, keeled longitudionally, half length of frons; labrum brown, sides plana te; labium brownish black, grooved medianally and longitudionally. Eyes opalescent reddish brown, orbits not pubescent. Thorax, average width 17 mm., yellowish brown; pronotum faintly sculptured, unicolorous with exterior margins edged black; three sulci on either side of median, posterior marginal band wide, transversely striate; mesonotum yellowish brown with black markings, anterior margins finely golden pubescent; close to median on each side a small triangular black marking anteriorly, dorso laterally another " 7 " shaped marking from anterior margin to external angle of cruciform elevation, and a black dorsal marking in its interior angle narrowing to a point at anterior margin. Cruciform elevation yellowish brown with a black median longitudional line, angles lightly silvery pubescent. Metanotum reddish brown. Wings, anterior, average length, male, 48-1 mm., width, 16-8 mm.; female, 48-2 mm., 16-8 mm. Clear vitreous, veins yellowish brown excepting costal which is brownish black. Posterior, male, 28-0 mm., 13-0 mm.; female, 27-5 mm., 12-5 mm. Clear vitreous with veins yellowish brown; 2a and 3a bordered brownish orange. Legs brown, unicolorous, lightly clothed with fine short silvery pubescence. Anterior femora with two sharply pointed spines of about equal size; posterior tibiae with five spines; three on inner side, the proximal at middle, third near distal, second just beyond half way between; two on outer side and approximately opposite one and three of inner row. Underside of thorax yellowish brown mid- ventrally, yellowish laterally, dusted with white tomentum. 272 REVISION OF GENUS THOPHA Abdomen black with pre-anal segment thickly invested with white tomentum; tympanal sacs brown, extending laterally almost to fourth segment; opercula pale yellowish brown, interior margins fairly widely separated! interior angles acutely rounded, exterior openly so. Underside of abdomen brownish black with some white tomentum along base of tympanal sacs and on ventral angles of sternites. Type: British Museum. THOPHA NIGRICANS Distant. Thopha nigricans Distant, 1910.—Ann. Soc. ent. Belg., 54: 415. n apparently rare or local /1n/J species recorded by Distant as (1910) being allied to T. sessiliba, but recorded as differing from thai species by the shorter and broader abdomen, strongly pedunculate cyv^ and black head and thorax. I am indebted to Mr. R. J. Izzard of the British Museum (Natural History) for structural details and figure of this cicada. He expresses the opinion with which I agree, that tins species is a colour variety ot T. sessiliba. It is recorded only from North Queensland, the precise locality not being given. Body length, male, 43 mm., female, 41 mm.; two specimens only examined Head uniformly deep purplish brown, slightly darker in the male- wider than pronotum. Ocelli purplish brown vitreous, almost equidistant; antennae deep purplish brown. Frons unicolorous with head and showing nine visible transverse ridges (both sexes); genae purplish brown, invested with greyish pubescence. Labrum brown, slightly over half length of frons; labium brown- eyes opalescent brown. Thorax, width, male, 18 mm., female 18 mm.; pronotum deep purplish brown, three sulci on either side of median, grooves and depressions pubescent, greyish. Mesonotum deep purplish brown, slightly pubescent in female, not so in male, excepting in grooves and sulci. Cruciform elevation purplish brown with greyish pubescence in depressed areas. Wings, anterior, length, male, 56 mm., width, 19 mm.; female, 56 mm., 17 mm.; clear vitreous with veins brownish yellow.